It would arguably give the actors more stuff to work with. As for the heavy stakes... I love epic epicness as much as the next guy, but that can only take you so far if you don't add charm to the equation. I'm curious, and a little concerned, as to how the Lois/Clark relationship will be after MOS. Will they already be in a steady relationship in the sequel? In my opinion, that was one of the weaknesses of the comics in the post-marriage era. Sexual tension is a huge asset, and without that... what are you left with, when it comes to Superman and Lois? I know I'd have trouble thinking of something. Hopefully Goyer manages to.

You can't keep denying the sexual tension though at some point it has to give. To you as the reader and the characters as well. Can't keep them stringing along other wise it gets boring and tiring.

There's been many a great story post marriage you have to get a writer good enough who can write them like that. It's on thing getting them to the point of being a couple another thing entirely writing after that.